The human body absorbs nutrients through the digestive system. Food is introduced through the mouth where a person's teeth masticate the food into smaller pieces. Saliva in the mouth begins the digestion of starch in the food. A person then swallows the food, transporting the food through the esophagus into the stomach. In the stomach, the food is mixed with gastric juice which begins the digestion of protein in the food. The stomach mixes the food with other enzymes. After a period of time, the pyloric sphincter opens at the bottom of the stomach allowing the food to pass into the duodenum where the food mixes with more enzymes. The food continues into the small intestine, where digestion continues and nutrients are adsorbed into the bloodstream. The large majority of the absorption of nutrients occurs in the small intestine. The remaining material is transported to the large intestine where water is absorbed before waste is eliminated from the body.
Reducing the ability of the body to absorb nutrients has been shown to be an effective means of weight loss and treatment of Type II diabetes. Past treatments for reducing the ability of the body to adsorb nutrients included gastric bypasses, in which a portion of the digestive system is bypassed, gastrectomy in which the functional volume of the stomach is reduced, and intestinal and/or stomach sleeves, in which the sleeves inhibit the absorption of nutrients. Current intestinal sleeves are placed proximate the pyloric sphincter, with part of the intestinal sleeve in the distal end of the stomach and part of the intestinal sleeve in the duodenum. Current devices may cause sores in the stomach and intestine from the intestinal sleeve rubbing and cutting into tissue as well as twisting and subsequent stricture of the sleeve.
It is difficult to anchor a device in the duodenum of a patient because the mucosal layer of the duodenum continually renews itself by sloughing off. Thus any attachment to the mucosal layer eventually fails as the mucosal layer sloughs. It would be beneficial to develop an intestinal sleeve that does not rub and cut into tissue, but is able to remain in place despite any sloughing of tissue adjacent the intestinal sleeve.